Well the litmus test would be to test it with a RAW recorder to see if the sensor and WB range is hampered. WB shifts color channels to boost the deficient colors. It could be the FS series has a sensor that is just skewed toward green channel to boost low light, and that means it just turns everything green/cyan underwater. And once you try to boost gain to compensate, noise comes out.

Drew
Moderator
"Journalism is what someone else does not want printed, everything else is public relations."

"I was born not knowing, and have only had a little time to change that here and there.

Drew I think you could be right with your theory, however it really isn't just a WB issue. You also have to throw into the ring significant amounts of digital noise on highlights even at 0db Gain, the complete destuction of any effective DR underwater with highlights completely blown out, super saturation of the images when shooting below 10m even when you reduce the in camera saturation in profiles and not to mention the weird Orange/Magenta/Red ring grain effect on lots of footage when white balanced at depths below 10m.

I've posted a screen shot below of the ring grain effect from an image that was white balanced at 20m with Gain set to 0db. It clearly shows this effect which shows up to a greater and lesser degree when you WB at depth and was responsible for ruining most of my footage from the FS100. From some testing I think this actually could be an issue with how the camera commnicates with the lens as when I have replicated this topside and unlocked the lens it has disappeared only to reappear when the lens is locked back into position. I've also read reports of a similar effect when shooting landscapes in low light so this is definitely not only showing up when shooting underwater. You can often get rid of the rings from the image by moving midtones and blacks over towards blue, but then you are just left with a very, very blue image.

I don't want to hijack a FS700 thread when most of this is refering to my experience with the FS100, but from all the evidence I've seen they are very, very similar cameras and this would be in line with the other problems experienced with the NXCAM range from Sony.

I still scratch my head and wonder how such a wonderful topside camera can produce these results and I'd LOVE to see some RAW results from an underwater test. As much as anything for my own sanity it would be great to work out exactly what on earth is going on with these cameras!

This is worrying but also intriguing at the same time. I wonder if this has anything to do with sensor temperature. the FS700 has same size sensor as the Scarlet or an Epic. A S35. I know Scarlet is not a low light demon. I perform a black balance to get rid of sensor noise. I am recording raw so I hardly WB with the camera UW. The deeper I go the dimmer the ambient light and less warm colour to record. I avoid crushing the blacks and if I use lights avoid clipping highlights. When I just use ambient light I get mostly blue footage without much red. The RGB histogram will clearly show R is clipped. As long as the image is exposed properly the G and B could still be used in post and pull something decent out of the image. Will be grainy as hell but not cyan badly as your example.

You could be right. Thee donut color pattern could be lens related or some reflection from some filter on the sensor. It looks like interference pattern. I wonder if you use older manual lenses and not electronically linked will this phenomenon goes away?

I don't have a whole lot of experience with the FS100 or FS700 underwater but land footage I've seen blew my socks off. If from what was discussed setting at 0 db gain the problem persists I am intrigued why the problem does not show up more on land shoots say at night scenes.

It would be a shame if there is no solution for this range of camera for UW. By avoiding AVCHD codex and using using RAW I hope this problem could be avoided. I think more investigation is needed.

It really is a conundrum David. I regularly shoot up to 24db topside and the footage is perfectly useable. Like I said I have only ever heard of this issue being replicated naturally topside on some low light landscape footage but I have been able to replicate it in low light topside by using the same MWB settings that were being using underwater. You can't use the preset WB settings as that is a whole other can of worms waiting to pop out. All my shooting was in ambient light but in conditions where the camera should perform well. I've had 7D's and PMW200's shooting side by side and the footage from them has been gorgeous in those conditions.

I would love to try a manual lens underwater but in the Genesis I'd have no way of controlling focus or aperature. With hindsight I have a Samyang 8mm fisheye that I could have set up to test with, but its too late now as I'll not be diving with the FS100 again apart from I may have a snorkelling shoot coming up that requires 1080p50 so it 'may' get a reprive for that.

Drew I've not sent it back, but it performs flawlessly topside and this issue is replicated with other FS100 and FS700's underwater so it is not unique to my camera. I've been in email correspondence with Sony Pro UK who so far have been as stumped as we are as to what it going on.

I spent the weekend dry test fitting the F55 with the Gates housing. My friend's F55 was working perfectly and system is very nice. The problem is still the on board software. Nothing to do with the operations of the camera more to do with incompatibility with certain post-production software. The F55 and F5 will have full feature operation by September including a better colourmetry and other presets. What was most interesting from the conversation was that in the beta stages the F5 and F55 have exactly the same issue with donut colour rings, strong colour shift and poor colour recovery when scenes are lit with predominately blue or red LED lights ie. in Rock Concerts etc.

All that has been solved by software update in the F5/F55 camera. Not a sensor issue as far as he know. However even if it is the sensor or OLPF or whatever Sony could solve it with software it seems. He also said that Sony knew about the problems with FS100, FS700 and F3. Why they do not fix it with Firmware is anybody's guess. My take on this is because of the F5/55 launch. Sony just don't want cross products cannibalization of sales until maybe F5/F55 have reach their quota. Cynical me. I guess more of us has to push Sony so that they will provide some fixes, I know UW shooters is nothing compared with number of topside shooters. I we could get more of them to ask Sony maybe this problem could be solved sooner. I am hopeful at least for FS700 as RAW recording is possible.

Nothing from Sony UK David, they have referred it to the engineers in Japan and are waiting for an answer.

Very interesting that you have said it had also been showing up on the F5/55!! Wow I had not expected that! I've had no problems at all with the PMW200 (which also suffers in blue LED light) but there were horrible reports about the fixed lens NXCAM cameras so it can't be confined to just the interchangeable lens range.

Wow now we are jumping into a confusing territory. It's a known issue with crappy (especially Blue/Red)LEDs, you get an uneven, spikey light that has all sorts of values that "look" good but crack under a spectrophotometer and trisimulus colorimeters analysis. I spoke about this in the video lights primer. The light from these crappy LEDs cause spikes in many colors in the spectrum and sensors can pick up nuances our eyes can't immediately but can see on a monitor.
So CRI isn't always accurate with LED. Alan Roberts, formerly of the BBC, has pushed for a more stringent test for color reproduction called TLCI (Television Lighiting Consistency Index). He tested 8 different cameras with LED and all the cameras didn't reproduce the color spectrum the same way, due to sensor variances. It's a well known phenomenon!
Could it be that the way sea water filters light replicate this behavior in sensors? I don't remember enough of optics physics to postulate that it can't, but I don't think it will cause spikes like LED, but more like a filter that takes out the warmer spectrum. But we do know that sensors respond to light differently, so it could be the Sony EXMOR CMOS process could have difficulty in the water filtered environment.
PS: I'm hoping to convince Dedo Wiegert to make a Dedolight for underwater use! He's been a big voice in the LED sensor phenomenon for years now.

Drew
Moderator
"Journalism is what someone else does not want printed, everything else is public relations."

"I was born not knowing, and have only had a little time to change that here and there.

Hmm Drew. Interesting about the LED spike. No idea yet and not sure if that is the same issue. Could be due to missing spectrum or clipped colour.

Look guys I would take everything said so far with a large dollop of salt. All I know is the guy who owns the F55 said the early testing of the beta version of the F5/F55 did show similar phenomena topside which is Blue or Red (Cheapo LED lights). Sony obviously fixed that problem for their flagship product. What was interesting was the fact it was a firmware fix.

Big hopes for "lesser" Sony cameras like the F3, FS700 and FS 100 and dare I say consumer camcorders. That is for UW footage. Most shooters aren't divers. The problems topside is not that prevalent. The number of UW shooters around the world is not enough to show up on Sony's radar.

Hoping we get topside shooters to ask as well then perhaps Sony may hear.

Simon

PMW 200 is three chip so the channels are probably get better processing. Single chip uses debayer and all sort of magic to mix the colours and really it is not an exact science.Even Red Epic does not show consistent results

Yes. During the shooting of the promo videos for the F55/F5 launch, they had people writing code on location overnight. Glad (or sad) to see Red's influence in alpha/beta ware is infectious!
Ok I've started to google this issue now and first page shows I'm not sure they fixed it::

Nino Lietner's music video for DEJA shows how bad the blue LED phenomenon is. The clearest example is @ around 2.01 where the blue light just goes crazy , whereas the Magenta stays normal.
Also @ 3.29 on the cup.

Oh and here's Nino's blog on the shoot... and if you read about the blue stage light issue, you'll see a shot @ Sony and a prop for Canon! LOL

Drew
Moderator
"Journalism is what someone else does not want printed, everything else is public relations."

"I was born not knowing, and have only had a little time to change that here and there.

Looking at the FS100 clip from Daniel, it seems he's using MWB for the shallow shots (the first few scenes in the video), but not the deeper wreck shots (I think that's the Capt Dan, which isn't more than 110ft (33m) deep I think). He says there's no filters used, which is why I asked Simon and Thani about their filter use. The results are pretty much in line with what was discussed in the FS100 WB thread.

I think part of the problem is that other cameras can do better MWB than the FS series. Most of them are smaller sensor video cameras, but DSLRs do well too.

Drew
Moderator
"Journalism is what someone else does not want printed, everything else is public relations."

"I was born not knowing, and have only had a little time to change that here and there.